1. Field of the Invention
This invention relates to a switchable attenuator and to a method of assembling same. More particularly, this invention relates to a switchable attenuator utilizing a split housing assembly formed of interlocking cover and support members, for providing attenuation to an external circuit and to a method of assembling the same.
2. Description of the Prior Art
In prior art attenuator structures, it has been common to provide attenuation to an external circuit utilizing a slideable attenuator assembly. The slideable attenuator assembly ordinarily includes a slideable arm having conductive contact members at each end thereof. The conductive contact members on each end of the slideable arm are selectively engageable with switching contact pads, connected to circuits on an attenuator circuit substrate, to complete circuit paths between circuits on the attenuator circuit substrate and thereby provide attenuation in the external circuitry. The very nature of the slideable attenuator assembly design requires that the conductive members and contact pads be engageable on the planar surface of the attenuator circuit substrate. As a result, a large amount of space is required in the plane of the circuit to accommodate switching.
In addition, utilizing this arrangement makes it necessary to provide switching contact pads which are made of conductive materials which insure very high reliability. Materials of this nature are required to insure the integrity of the electrical connections established between the conductive contact members on the slideable arm and the switching contact pads. This requirement is most often satisfied by utilizing very precious conductive materials to form the switching contact pads such as, for example, gold and/or rhodium. The space requirements and the quantity of precious conductive materials that must be used results in an expensive attenuator structure. Accordingly, it is desirable to provide a reliable attenuator structure which does not require the space and quantity of conductive materials required in manufacturing the aforementioned attenuator structure.